A Trick!
If faced with a large binary number that has to be converted to decimal, I first convert the binary number to HEX, then convert the HEX to decimal. Less work!
% 110111110011 = % 1101 1111 0011 = $ D F 3 = 13 x 162 + 15 x 161 + 3x160 = 13 x 256 + 15 x 16 + 3 x 1 = 3328 + 240 + 3 = 3571
Of course, you can also use the binary, hex conversion feature on your calculator. Too bad calculators won’t be allowed on the first test, though…...